OK. More thought will be required here.

...skill in metal work or access to such technology.

Both. Possibility exists to go directly from .dwg to CNC laser cutting. Buy some metal and call in a favor.

...open baffle application

I just can't go back to boxes. I'm running NSB/PT-2 arrays now and filling in the bottom with Tuba 18's. I like it. The arrangement would be similar for the planned 34 driver baffles.

...no BSC for open baffle but dipole compensation.

Understand.